Uploading a synthetic data in Geopsy: File cannot be read!

[Pourya]

Hello all,


I am trying to upload a synthetic data file in txt format, but the geopsy is not reading it ( the data is not being transferred automatically in geopsy tables). This is while the file can be read in other similar software.

Then I thought that maybe it is better to upload an SG2 file instead of txt. Here I have two questions:

1) Is there any way to easily convert "txt" to " SG2"?

2) Is there any specific format for the "SG2" file that we need to consider while making it ( like having a specific header, etc.)------- after struggling with this, I finally could convert to SG2 format and geopsy could read it, but I faced with a bigger problem. All the data points are considered high energy points in the dispersion curve, and the dispersion image is completely blue ( The picture is attached).

BTW, I wanted to upload my txt and sg2 files, but the forum is not accepting the format and size of them.

Sincerely,
Pourya

[Pourya]

I could attach the SG2 file in a compressed format.

[admin]

Hi,

To read a text file (data organized in columns), data must begin from the first line. In your case (sent by email) the first lines are:

Code: Select all

48 16384
 0.000000e+000  4.858683e-010  ... [total=49 columns] ... -5.356799e-011 
 1.250000e-004  4.145977e-010  ... [total=49 columns] ...  2.776331e-011 
... [total=16385 lines]

You have to remove the first line containing the number of columns and lines. Load the file into geopsy.
49 traces will be available (display them in a table). At this step, displaying them in a graphic will not produce anything because the starting time is not properly set.

The starting time in the table is "####-##-## 00:00:00.000000" which is an invalid time. Go into menu "Edit/Set headers". Enter the following script to modify the starting time of all signals:

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for(i=0; i<signals.length; i++) {
  signals[i].startTime="200001010000";
}

Click on "Apply" and now the signal are visible in any graphic viewer.

The default sampling frequency is 100 Hz. The sampling period can be read from the first column of your file: 0.000125 s, hence 8000 Hz. Again use "Set headers" for modify this property. Here is the script to modify everything in a single step:

Code: Select all

for(i=0; i<signals.length; i++) {
  signals[i].startTime="200001010000";
  signals[i].samplingFrequency=8000;
}

Select only the last 48 traces in a table and drag them to a new graphic viewer. The first signal containing the time is useless. Work only with the last 48 traces.

Best regards,

Marc

[Pourya]

Dear Marc,

Thank you for your swift response. I did what you said and changed the name and spacing for the stations as well, but still, the f-k process is not working to give me the dispersion image. I noticed that When I select the data, the figure showing the station-spacing information is covered in red, which must show something:

1st.JPG

(143.06 KiB) Not downloaded yet

I searched about it on your website, but nothing is mentioned there. As I said, nothing appears when I click on start for the f-k process:

Second.JPG

(99.15 KiB) Not downloaded yet

I would be grateful if you can clarify this problem.

[admin]

What is the release number you are using?
I remember that I fixed a bug during this Summer about the modification of the starting time and the update of the available range. The available range keeps track of eventual gaps inside a trace (a period of time where no processing can take place). Having everything in red means that the complete trace is a gap, hence no processing is possible. If you are running 3.3.2, I'll check exactly when it was fixed and if necessary, I will publish next release (3.3.3) as soon as possible.

[Pourya]

As you guessed, I am using version 3.2.2...
Thank you for your responsibility and swift response.